The present invention generally relates to medical imaging. In particular, the present invention relates to systems and methods for proactive detection of imaging chain problems during normal system operation.
Imaging systems encompass a variety of imaging modalities, such as x-ray systems, computerized tomography (CT) systems, ultrasound (US) systems, electron beam tomography (EBT) systems, magnetic resonance (MR) systems, and the like. Imaging systems generate images of an object, such as a patient. The images may be generated, for example, through exposure to an energy source or wave. For example, ultrasound beams may travel into a patient and produce echo signals reflected from bone and tissue inside the patient. As another example, an x-ray source may be used to generate x-rays that pass through an object. The x-rays may be partially absorbed by the object and an image may be generated based on the energy that passes through the object.
The generated images may be used for many purposes. For instance, internal defects in an object may be detected. Additionally, changes in internal structure or alignment may be determined. Fluid flow within an object may also be represented. Furthermore, the images may show the presence or absence of structures in an object.
The images generated by medical imaging systems may be used to assist a physician in making an accurate diagnosis. For example, a physician may use one or more images to visually identify a lesion or other anomalous structure in a patient. As another example, a physician may compare images taken over a series of patient visits to examine the evolution of a structure and/or to evaluate the effectiveness of a treatment. That is, the physician may examine morphological changes, such as changes in size and/or shape, of a lesion to evaluate its characteristics and/or the effectiveness of therapy.
In an ultrasound imaging system, for example, a sequence of beams or sound waves is generated by a probe. The transmitted waves are reflected or scattered from the object being scanned. Some of the waves may only be partially reflected. The reflected signals are received by the probe. The received signals are then read out from the probe and processed to create a digital image.
The ultrasound beams generated by an ultrasound imaging system are based on a scan sequence. The scan sequence includes a series of vectors that specify the parameters of the beam to be generated by the probe. The parameters may include amplitude and direction, for example. The vectors may be based on the kind of image desired and/or an scanning mode. For example, in a B-mode image, the scan sequence may specify a series of vectors to fan the beam through a plane to generate a two-dimensional image. As another example, a pulsed wave mode may be used for examining blood flow. A scan sequence may include and/or mix different kinds of vectors. For example, a scan sequence may include 100 B-mode beams mixed with 86 color beams.
Another type of vector that may be included in a scan sequence is a “junk” or “conditioning” vector. A junk vector may be used to set up initial conditions for subsequent vectors and/or when switching modes. A junk vector may be fired when it is desirable for a subsequent vector to have acoustic energy in tissue, for example. For example, in a sequence of color firings 0 through 10, a junk vector may be added to the sequence at firing −1, yielding the same side-effects regarding acoustic energy in the tissue for the actual color firings.
The reflected signals from the beams are received by the ultrasound probe. The reflected signals are then processed by the imaging chain of the ultrasound system. That is, the signals are read out of the transducer of the probe and then processed to generate one or more images.
Current medical imaging systems, such as ultrasound systems, may include system diagnostics that reside on the system for assessing problems with imaging performance. Such diagnostic systems are passive. That is, a field service person and/or operator must manually invoke the diagnostics. For example, a field service engineer may manually invoke one or more diagnostic checks either in person or remotely. Running these diagnostics results in downtime for the users of the system. In other words, while the diagnostic system is being utilized, the imaging system cannot be used for its normal operations. Thus, it is highly desirable to have an active system-health monitoring capability that runs when the system is being used for normal operations.
Certain aspects of an imaging system may be easily monitored. For example, power supply voltages, system temperatures, or the data error rates of a network connection may be relatively simple to check the status of. However, current systems are unable to actively monitor the status of the image chain. That is, failures, errors, and/or artifacts in the imaging chain that may be indicative of larger or developing system failures are not easily monitored in current systems. Thus, it is highly desirable to be able to actively monitor the status of the image chain.
Therefore, there is a need for an active system-health monitoring capability that runs when the system is being used for normal operations. In addition, there is a need for the ability to actively monitor the status of the image chain. Thus, there is a need for systems and methods for proactive detection of imaging chain problems during normal system operation.